Wireless telegraphy.



F. a. SIMPSON. WIRELESS TELEGRAPIIY. APPLICATION FILED APR. 23, I913.

1,189,881. v Patented July 4, 1916.

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UNITED sTATEs PATENT o EIoE.

FREDERICK e. srnrsoiv, or sEATTLE,.wAsnmeTo1v.

WIRELESS IELEGRAPHY.

. t Specification of Letters Patent. I

Patented July 4, 1916.

Original application filed Rover. )er 1,' 1912, Serial No. 729,064. Divided and this application filed April 23, 1913. Serial no. 763,142.

Be it known that I, FREDERICK G. SIMP- SON, a citizen of'the United States, residing at Seattle, in the county of King and, State of Washington, have invented certain new and useful Improvements in Wireless Teleg-" which the, following isa specification.

This application is a'division of one filed by me Nov. 1, 1912, Serial No. 729,064.

The invention herein disclosed relates to certain improvementsin circuiting and ap paratus for the reception of signals of the Hertzian wave type. d

The present invention has for its object the provision of a new. and improved means for detecting the existence'fofand utilizing to the best advantage voltages or currents in wireless telegraph receiving circuits, which have been generated within such circuits by the passage of a train of Hertzian waves The invention therefore consists in the circuiting and arrangement and combination of apparatus therein substantially as hereinafter set forth and claimed;

In the accompanying drawing which forms a part of this specification, Figure 1 d agrammatically depicts the improved circuiting and the principal features of the receiving instrument. employed therewith;

and Fig. 2 is a. transverse sectional view of the electromagnet in the main receiving circuit. i

For amore complete description of the details of said instrument reference may be had to my earlier application above referred to. I p:

In the graphicillustration of the receiving circuit, 30' and 30" indicate parzdicl,

magnetizable, vibratory reeds fixed at one end and attached at the other to an adjustable block 31 of insulation. attached to the crosshead 37 mounted in frame 34 and is adjustable by means of screw 30 and spring 35. Thus the tension of the reeds may be regulated. The slides 11 carry arms 14, which bear against the reeds.

These slides are joined by a left and right hand screw 44 by which they may be adjusted toward and from one another to vary the length of the portions of the reeds left free to vibrate. The microphoni'c contacts a and b, actuated' y the reeds are. on the ends of the-pins 16"1-af1d16". The char'- acteristics of other features of the apparatus This block is and circuiting will be described in the detalled operation of the invention.

The aerial here shown is of the antenna form indicated at 52, towhich is connected the variable inductive coupling-having a primary 51 and a secondary 51 The antenna 52 isgrounded through primary 51 of the inductive coupling 51.. .Hertzian waves arriving at'the antenna'induce voltages therein, which cause high frequency oscillating currents to flow through the antenna and the primary to and from the earth. These currents, by inductive action through the coupling 51, produce voltages within the secondary,.'or main receiving circuit. containing the coil 51 the fixed condenser 53, the solenoid coil of helix 19; and the electro-magnet coil 17, whose core con sists offine individually insulated iron wires, Fig. 2. The primary 51 and sec- .ondary 5-1 permit of adjustment of induc frequency on rent over said receiving circuit. I

- v A crystal detector of well-lmowntype is indicated at 61 connected in parallel circuit with the coils. 19 and 17 of the micro-magnetic detector.

1 ere-magnetic detector is especially efiective in forming a means of adjustment for some In this association the mi particular wave train frequency, and also as a means of amplifying the strength of the received signal by its action as arelay,

permitting energy from the battery or other electrical generator 57-, to furnish energy required by the telephone receiver 59 or other indicating instrument in its production of audible or visible signals. By this use of the crystal detector, unidirectional pulsating currents only are permitted to flow through coils 19 and 17. The; action ofa pulsating current, flowing through saidcoils, upon the reeds 30;a nd 30" is to all practical purposes the sauie as is that of an alternating current of the samefrequency.

Reed 30 lies within the magnetic field of the electro-magnet coil 24 wound about the adjustable core 23. This magnet is excited by current from battery 56. The voltage at the terminals of coil 24 is capableof adjustment throughthe medium of thereg'ulating rheostat 55. The density ofthemagnetic I field in 'thevicinity of'30" can be regulated by variation of the exciting current and also by movement of the core 23.

Pulsating currents of high frequency'flowing through coils 19 :nd 17 produce motion in' the reeds 30 and 30. In the absence of these currents the reed 30 is moved slightly away from its position ofnornial rest by the magnetic attraction of the core of magnet 2%, and a state of magnetic polarity exists within the reed 30 at a point opposite core 23. Magnetism is also communicated to a lesser degree to the core of coil 17. Upon the arrival of a series ofHertzian waves, high frequency pulsating currents flow through coils l9 and 17, which in eiiect partially suppress'themagnetic condition of the: reed 30 and the core 18, respectively,

. permitting reed 30 because of mechanical tension thereon to recede slightly from the magnet core 23. At the same instant the high frequency currents flowing through coil 17. induce within the core 18 an oscillating magnet flux, which has an integrating tendency to attract reeds 30 and 30 to its extremities. These phenomena are simultaneous in their action and have a tendency to draw said reeds closer together, the eby decreasing the resistance at the microphonic contacts a and 7), which permits an increased flow of current from the generator 57 through the reeds, the pins 16' and 16", the microphonic cont-acts and the'primary ot' transformer 58. This increase of current by inductive action produces a voltage be tween the secondary terminals of the transformer 58 thereby causing current to flow in the secondary to produce an audible signal.

in the receiver 59. As each series of Hertzian waves communicate but a single iinpulse to the reeds, each will, if properly proportioned, vibrate at the frequency of the wave trains, e. at the same rate per second of vibrations as is the rate per second in the number of wave trains arriving at the receiving station. For the purpose of securing the greatest eiiicicncy in operation of the microaaiagnetic detector described, it

' is necessary that thereeds be of such dimensions that their natural period of vibration shall be the same as' the frequency oil the incoming Wave trains. Then by the use of proper adjusting devices the active lengths and tension of the reeds may be so regulated that the reeds-will respond accurately to wave trains. arriving at a preselected frequency and will not be allccted by wave trains arriving at a different frequency. This adjustment to the frequency of wave trains is entirely mechanical and should not be confounded with the adjustment for electrical resonance by properly proportioning the capacity and inductance in the receiving circuit, which adjustment is entirely electrical and is made for the frequency of the oscilla' tions within the wave trains themselves, or in other words for the wavelength of the Hertzian waves.

The invention claimed is 1. In a. wireless telegraph system, the combination vith an antenna and a receiving circuit, two suitably supported-reeds made of magnetizable mati ial, a helix surrounding a portion of one or said reeds, an electromagnet in the receiving circuit disposed to extend between said two reeds so that each 'of the poles of its core may be adjacent to one of said reeds whereby said electro-niag net may be operated to attract said reeds to bring them nearer to each other, said helix and electromagnet being in series in the receiving circuit, microphonic' contacts operated by said reeds, a condenser connected with said circuit in series with said helix and said electro-magnet, a detector connected with said circuit in parallel with said helix and said electro-magnet, and asignal controlled by the microphonic contacts.

2. In a wireless telegraph system, the combination with an aerial and a receiving circuit derivingcurrent therefrom, of a crystal detector in parallel with the receiving circuit, a vibrator, an actuating electro-magnet therefor consisting of a coil of line wire in series in said circuit and having a core of fine individually insulated iron wires, a condenser in said circuit in series with said coil, and a helix in series with said coil for magnetizing said vibrator, the helix and coil in series with said. receiving circuit.

3. In a wireless telegraph system, the combination with an aerial and a receiving circuit deriving cur'ent impulses therefrom, a receiving instrument having a vibratory magnetizable reed, a helix in said circuit surrounding said reed, an electro-niagnet whose coil is in series with said helix and whose core is a bundle of fine individually insulated iron wires located to attract said reed, and a condenser in said circuit in seties with said coil, of a crystal detector in parallel with said coil and said helix.

4. In a wireless telegraph-system, the combination with an-aerial and receiving circuit deriving current'therefrom, aI-vibrator forming part of a micro-magneticreceiving instrument, a movable helix in said circuit and surrounding a portion of said vibrator for magnetizing it, an electro magnet whose coil is in series with said helix and whose core is abundle of fine individually insulated iron wires located to attractsaid vibrator, and ,a condenser in said circuit in series with said coil, of a crystal detector in parallel with said coil, and a separate circuit inseam ceiving circuit and surrounding a portion of said element, an electro-magnetn the receiving circuit and having one of its poles adjacent to said. element, whereby jwhen rectified electro-magnetic waves exist-in the receiving circuit the helix and electro-magnet are.caused to directly vibrate said"element, means in a separate" circuit toproduce a magnetic field of predetermined polarity in and adjacent to said element, microphonic contacts operable by said clef -rnent, and a signal operated-by said. con-1 tacts. V -6. In a wireless telegraph syste' the combination w th an antenna. and a re,

ceiving circuit,'two suitably supported reeds made of magnetizable 1naterial,-a helix surrounding a portion of one of said reeds, an electromagnet in the receiving circuit disposed to extend between said two reeds so that each of the poles of its core may be.

adjacent to one of said reeds whereby said electromagnet may be operated toiattract said reeds to bring them nearer to each 'other, said helix and electromagnet being in series with the receiving circuit, microphonic contacts operated by said reeds, indicating means controlled by said contacts, a condenser connected with said circuit in series with said helix and said electromagnet, of a detector. connected with said circuit in parallel with saidl'ielixand said electromagnet, and a signal controlled by the microphoniccontacts.

, 7. In a wireless telegraph Lsystem,I the. comblnation with an aerial and a receiv ng circuit, of a detector in parallel with the adjustable magnetizable reed provided with microphonic contacts, a signaling circuit connected with said contacts, means in the receiving circuit to vary the hysteresis in and to directly actuate, said reed on the passage of electromagnetic waves,-adjustable means ina separate circuit to produce a desired degree of magnetization in said element, and a'condenser in series with said v means in the receiving circuit.

9. ln a I wireless telegraph system, the

Copies of this patent may be obtained for combination with an aerial and a'receiving circuit, of a detector in parallel with the receiving circuit associated with a plurality of magnetizable reeds, indicating means controlled by said reeds, a movable helix surrounding a portion of one of the reeds, an

electromagnet 'in-series with'the helix and the" recei-ving circuit to directly vary the 4 hysteresis of emer ed, means in a separate circuit to producea predetermined polarity at magnetism "adjacent to. and whose field includes the reed, whereby 'on the passage "of'electromagnetic wavesthrough the re- ,ceiving circuit, the helix and electromagnet ,are caused to' rapidly vary,- the hysteresis, and a condenser in, series with the helix and electromagnet.

"combination with anj aerial and a: receiving {circuiqof a detector'in jparallel with the reeeivingcircuit associated with a magnetizable and.- at ]ustable vibr'ato'r element, indicating means-controlled by said. egement, means in the receiving circuit *toa immediately magnetiz'e different portions thereof and to directly actuate said element by recl tified electromagnetic waves, a separate cir- 10. In a wireless system, the p cuit, means in the" separate circuit to pr0- duce a magnetic field to saide'lement, -wherc-' by on the passageof electromagnetic waves through the means in the receiv ng circuit,

the integrating effect produced by varying the hysteresis in theyelement is to cause said element to vibrate at its free frequency corresponding to the frequency of the electromagnetic wave: trains? impressed, and. a

condenser'in series withthe receiving circuit.

11. In a wireless telegraph system, the combination With an aerial-and a receiving circuit, of a detector in parallel with the receivingcircuit associated with a plurality of adjustable reed vibrator elements capable of magnetization, signalingmeans controlled by said elements, a'plura-lity of instrumen- .ta-lities in the receiving circuit to produce magnetic polarities in separate and distinct portions thereof and capable of actuating said element by thepassage of electromagnetic'wave trains, means'to magnetize another portionof said element by roducing a-magnetic field of pro-determine polarity jadjacent thereto, and a condenser in series with said instrumentalities in said recciv ing circuit.

' Signed at Seattle, of April, 1913. 4 I FREDERICK G. SIMPSON.

Witnesses: n

PIERRE BARNES, E. PETERSON.

Wash, this 15th day five cents each, by addressing the Commissioner of Patents,

Washington, I). (1. 

